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authorMark Brown <broonie@kernel.org>2023-07-17 08:12:31 +0300
committerMark Brown <broonie@kernel.org>2023-07-17 08:12:31 +0300
commit0791faebfe750292a8a842b64795a390ca4a3b51 (patch)
tree0e6095a5a0130398b0693bddfdc421c41eebda7c /kernel/ksyms_common.c
parente8bf1741c14eb8e4a4e1364d45aeeab66660ab9b (diff)
parentfdf0eaf11452d72945af31804e2a1048ee1b574c (diff)
downloadlinux-0791faebfe750292a8a842b64795a390ca4a3b51.tar.xz
ASoC: Merge v6.5-rc2
Get a similar baseline to my other branches, and fixes for people using the branch.
Diffstat (limited to 'kernel/ksyms_common.c')
-rw-r--r--kernel/ksyms_common.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/kernel/ksyms_common.c b/kernel/ksyms_common.c
new file mode 100644
index 000000000000..cf1a73cbf2f6
--- /dev/null
+++ b/kernel/ksyms_common.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ksyms_common.c: A split of kernel/kallsyms.c
+ * Contains a few generic function definations independent of config KALLSYMS.
+ */
+#include <linux/kallsyms.h>
+#include <linux/security.h>
+
+static inline int kallsyms_for_perf(void)
+{
+#ifdef CONFIG_PERF_EVENTS
+ extern int sysctl_perf_event_paranoid;
+
+ if (sysctl_perf_event_paranoid <= 1)
+ return 1;
+#endif
+ return 0;
+}
+
+/*
+ * We show kallsyms information even to normal users if we've enabled
+ * kernel profiling and are explicitly not paranoid (so kptr_restrict
+ * is clear, and sysctl_perf_event_paranoid isn't set).
+ *
+ * Otherwise, require CAP_SYSLOG (assuming kptr_restrict isn't set to
+ * block even that).
+ */
+bool kallsyms_show_value(const struct cred *cred)
+{
+ switch (kptr_restrict) {
+ case 0:
+ if (kallsyms_for_perf())
+ return true;
+ fallthrough;
+ case 1:
+ if (security_capable(cred, &init_user_ns, CAP_SYSLOG,
+ CAP_OPT_NOAUDIT) == 0)
+ return true;
+ fallthrough;
+ default:
+ return false;
+ }
+}